My t.v comes on and show good picture but the background is green and I can't get all my cable channels

Purple Panasonic PC>TV Problem:
The VGA cable uses three primary color RGB channels.
Red, Green, and Blue.
The picture is made up of pixels or dots arranged in a grid along the "X" horizontal axis and "Y" vertical axis.
The computer mixes the intensity of each color channel to create a unique color per pixel.
All RGB at 100% creates white.
R+G creates yellow.
R+B creates magenta, ie purplish.
G+B creates cyan.
So a purplish tint sounds as if your Green wire has no signal, which may indicate a faulty VGA cable or VGA socket.
Put another way, (R+G+B)-G=R+B=magenta.
So try another VGA cable, spray all socket pins with "Servisol " or similar contact cleaner.
0%<--------->100%
Cyan<------->Red
Magenta<--->Green
Yellow<------>Blue
All 0%=Black; All 50%=Grey; All 100%=White.

Here are a few more troubleshooting steps you can try when your TV picture is just snow. I see that you have already rebooted your TV, but did you turn your set-top box off and on, too?

1. Does the picture show when you play a DVD?
2. Check all of the connections between the TV, outlet and set-top box and make sure everything is secured.
3. Is your TV set to the correct channel (typically 3, but in some areas 2 or 4)?
4. Press any key on the remote to see if the correct mode lights up. (Ex: if you have cable, the cable button should light up). If it doesn't, press the correct mode's button to regain control and change channels.
5. Call your service provider and make sure it's not an overall service outage.
6. Do you have sound but no picture? If so, it could mean a backlight failure.

For more suggestions, see TV black screen or snowy screen for troubleshooting and solutions. I hope this helps!

Check the connecting cables.

Unfortunately, I'd have to say that there's something wrong with the camera. The blue channel is going too high (or the red and green channels are too low). Take it in to a service shop and have them look at it.
Sorry.

This is the best solution for your problem as a 40 year experience with wires etc. Go to the source of your cable signal connector . Open it and clean the terminals with emery paper , sand the end of the cable shiny clean from corrosion , get a new barrel connectors with gold terminals if possible lengthen the ends of the cable , insert and tighten good, use thick rg-16 or rg 40 cable with good insulation ends crimped professionally with a crimpier or buy ready made , not from dollar store. Get a gold plated professional splitter if you need one or two , it will cost about 15 or more each . Make the cable runs as short as possible, using the thick good cables. If needed get a signal magnifier. From radio shack or the source etc. Connect them good and tight . Ground the splitters . Problem solved , you will get crystal clear channel 2 to 7 including 3 and 4 . Isolate the TV cable from other cables and power wires. Vitally

replace the analog board

The 37" Vizio I just bought has a very confusing feature where the same input can be used as either the Y channel of the component or the full video channel for composite. If you plug a component source into the TV and then select the composite input ("AV" on the remote), you will see a black and white version of the full component signal (makes sense as the Y channel is just the luminance component). As sad as it is, I was stumped by this for a while until I happened to hit "COMP" and got full color. FWIW, the manual warns about this, but it really doesn't emphasize the point. I wonder how many returns they get because of this.

Problem solved. I tried playing DVD and the TV picture was fine. So I double-checked cable wires from cable box - one of the wires was loose (obviously it was the red color input). After tightening, the TV picture is good as new.

Check your component cables. You have 3 colors coming in. Red,Green and Blue. Make sure the Red cable is good. You can do this by substituting the red cable only, or just change all 3 cables

Best regards
CircuitCity

i think this is the called picture in jail. this might be due to 1 power supply reg.poor or filter cap dry. 2 loose or dry joint nera hor. output section or capacitor in eht section.